xmerl_xsd(3erl) Erlang Module Definition xmerl_xsd(3erl)
NAME
xmerl_xsd - Interface module for XML Schema validation.
DESCRIPTION
Interface module for XML Schema validation. It handles the W3.org spec-
ifications of XML Schema second edition 28 october 2004. For an intro-
duction to XML Schema study part 0. An XML structure is validated by
xmerl_xsd:validate/[2,3].
DATA TYPES
filename() = string():
global_state():
The global state of the validator. It is representated by the
#xsd_state{} record.
option_list():
Options allow to customize the behaviour of the validation.
Possible options are :
{tab2file,boolean()}:
Enables saving of abstract structure on file for debugging pur-
pose.
{xsdbase,filename()}:
XSD Base directory.
{fetch_fun,FetchFun}:
Call back function to fetch an external resource.
{fetch_path,PathList}:
PathList is a list of directories to search when fetching files.
If the file in question is not in the fetch_path, the URI will be
used as a file name.
{state,State}:
It is possible by this option to provide a state with process in-
formation from an earlier validation.
EXPORTS
file2state(FileName) -> {ok, State} | {error, Reason}
Types:
State = global_state()
FileName = string()
Reads the schema state with all information of the processed
schema from a file created with state2file/[1,2]. The format of
this file is internal. The state can then be used validating an
XML document.
format_error(L::Errors) -> Result
Types:
Errors = tuple() | [tuple()]
Result = string() | [string()]
Formats error descriptions to human readable strings.
process_schema(Schema) -> Result
Equivalent to process_schema(Schema, []).
process_schema(Schema, Options) -> Result
Types:
Schema = string()
Result = {ok, State} | {error, Reason}
State = global_state()
Reason = [ErrorReason] | ErrorReason
Options = option_list()
Reads the referenced XML schema and checks that it is valid. Re-
turns the global_state() with schema info or an error reason.
The error reason may be a list of several errors or a single er-
ror encountered during the processing.
process_schemas(Schemas) -> Result
Equivalent to process_schema(Schemas, []).
process_schemas(Schemas, Options) -> Result
Types:
Schemas = [{NameSpace, string()} | Schemas] | []
Result = {ok, State} | {error, Reason}
Reason = [ErrorReason] | ErrorReason
Options = option_list()
Reads the referenced XML schemas and controls they are valid.
Returns the global_state() with schema info or an error reason.
The error reason may be a list of several errors or a single er-
ror encountered during the processing.
process_validate(Schema, Xml::Element) -> Result
Equivalent to process_validate(Schema, Xml, []).
process_validate(Schema, Xml::Element, Opts::Options) -> Result
Types:
Schema = string()
Element = XmlElement
Options = option_list()
Result = {ValidXmlElement, State} | {error, Reason}
Reason = [ErrorReason] | ErrorReason
Validates a parsed well-formed XML element towards an XML
schema.
Validates in two steps. First it processes the schema, saves the
type and structure info in an ets table and then validates the
element towards the schema.
Usage example:
1>{E,_} = xmerl_scan:file("my_XML_document.xml").
2>{E2,_} = xmerl_xsd:validate("my_XML_Schema.xsd",E).
Observe that E2 may differ from E if for instance there are de-
fault values defined in my_XML_Schema.xsd.
state2file(S::State) -> ok | {error, Reason}
Same as state2file(State,SchemaName)
The name of the saved file is the same as the name of the
schema, but with .xss extension.
state2file(S::State, FileName) -> ok | {error, Reason}
Types:
State = global_state()
FileName = string()
Saves the schema state with all information of the processed
schema in a file. You can provide the file name for the saved
state. FileName is saved with the .xss extension added.
validate(Xml::Element, State) -> Result
Equivalent to validate(Element, State, []).
validate(Xml::Element, State, Opts::Options) -> Result
Types:
Element = XmlElement
Options = option_list()
Result = {ValidElement, global_state()} | {error, Reasons}
ValidElement = XmlElement
State = global_state()
Reasons = [ErrorReason] | ErrorReason
Validates a parsed well-formed XML element (Element).
A call to validate/2 or validate/3 must provide a well formed
parsed XML element #xmlElement{} and a State, global_state(),
which holds necessary information from an already processed
schema. Thus validate enables reuse of the schema information
and therefore if one shall validate several times towards the
same schema it reduces time consumption.
The result, ValidElement, is the valid element that conforms to
the post-schema-validation infoset. When the validator finds an
error it tries to continue and reports a list of all errors
found. In those cases an unexpected error is found it may cause
a single error reason.
Usage example:
1>{E,_} = xmerl_scan:file("my_XML_document.xml").
2>{ok,S} = xmerl_xsd:process_schema("my_XML_Schema.xsd").
3>{E2,_} = xmerl_xsd:validate(E,S).
Observe that E2 may differ from E if for instance there are de-
fault values defined in my_XML_Schema.xsd.
AUTHORS
<>
xmerl 1.3.25 xmerl_xsd(3erl)